Modern motor vehicles are usually provided with self-supporting bodywork, which allows a reduction in weight and costs compared to bodywork constructed on a frame. In the self-supporting bodywork, the components absorb the introduced forces in their entirety, the stiffness of the bodywork being achieved by hollow sheet-metal cross-sections and a compact sheet-metal outer skin. A spatial separation between the passenger compartment and the front vehicle structure is provided by a partition wall disposed transversely to the longitudinal direction of the vehicle. The front vehicle structure usually comprises a front frame, which is used for fastening various vehicle components such as cooling module, engine mounting, battery holder, ABS holder, and the like.
Front frames are built into motor vehicles in manifold ways. For example, in one type of construction implemented by the applicant in automobiles of the “Opel Corsa” type, the front frame comprises two longitudinal members that are connected to one another at their front-side ends by means of a bumper cross member and which are connected to the under floor of the bodywork at the rear by means of downwardly bent extension profiles. This measure provides a crash load path by which forces absorbed by means of the bumper cross member in the event of a frontal collision are introduced into the under floor and side skirt structure. As a result of an additional connection of the longitudinal members to the partition wall, the absorbed forces can also be diverted via the lateral bodywork structure. Merely in addition, it should be noted that a plurality of crash load paths are usually formed in modern motor vehicles.
In almost all motor vehicles, a cooling module around which the wind produced by traveling flows is accommodated behind the bumper cross member on the front vehicle structure. Components of various cooling systems of the motor vehicle are combined in the cooling module in a space-saving manner. Cooling modules can in particular comprise the areas of engine cooling (heat exchanger), intercooling, and air-conditioning system (condenser), wherein suitable coolants are used for this purpose. In addition, a fan driven mechanically via the crankshaft or electrically can be provided, which serves to support the cooling effect of the wind produced by traveling and for cooling the internal combustion engine when stationary. In industrial series production the cooling module is installed as a prefabricated component on the production line.
If, in the event of a frontal collision of the motor vehicle with an obstacle, the bumper cross member is displaced backward in the direction opposite to the direction of travel, the cooling module itself can be severely damaged even at relatively low impact speeds, which requires a cost-intensive repair of the cooling module in the case of rather slight bodywork damage. In addition, if the cooling module is damaged, the vehicle is usually no longer drivable, for example, if coolant has escaped, so that further costs can be incurred for removing the vehicle involved in the accident to a workshop. In addition, the damage caused to a motor vehicle in the case of a collision is an important aspect for the classification into the various insurance classes, which can have the consequence that the motor vehicle is classified relatively unfavorably.
This problem has already been taken up in the patent literature. For example, the German Patent Application DE 102007020914 A1 of the applicant discloses a generic frontal structure for a motor vehicle, in which a frame is provided as a support structure for a radiator, which in the event of a collision-induced backward yielding of the bumper cross member, comes in contact with the bumper cross member earlier than the radiator so that damage to the radiator can be avoided.
In view of the foregoing, it is at least one object to further develop a general frontal structure for a motor vehicle in an advantageous manner. In addition, other objects, desirable features and characteristics will become apparent from the subsequent summary and detailed description, and the appended claims, taken in conjunction with the accompanying drawings and this background.